Newark mayor Cory Booker’s father, Cary, died Thursday morning at the age of 76. He had suffered from Parkinson’s disease and recently had a stroke. He died in Las Vegas.

Mr. Booker, who is running in a special election Wednesday for an open U.S. Senate seat, canceled afternoon campaign events Thursday, his campaign confirmed. The Democrat was scheduled to attend an afternoon rally with Monmouth County members of the party and state Sen. Barbara Buono, who is running for governor.

Born in North Carolina to a single mother, Cary Booker was active in the civil rights movement. He and his wife, Carolyn, were two of the first black executives at IBM in the 1960s. They lived in Washington, D.C., where Mr. Booker was born in 1969, before moving to New Jersey.

They raised Mr. Booker and his older brother, Cary, in Harrington Park, a largely white borough in Bergen County. They joined Mr. Booker—who was elected mayor in 2006—in living in Newark in recent years.

“Many people in our city came to know and love Cary Booker. Mayor Booker’s father was an inspiration to him, and someone the mayor has often credited with being a principal reason for him entering public service,” said the city administration in a statement.

“Housing rights activists helped the family buy their first home after initially being turned down because of the color of their skin,” Mr. Booker said on his campaign website.

Mr. Booker often mentioned his father’s path of pulling himself up from poverty in speeches. He brought his parents on a “trip of a lifetime” to Israel in 2011.

“It brought us to tears,” Mr. Booker said during a speech in Hamilton, N.J. last year.

Mr. Booker faces Republican Steve Lonegan in the Oct. 16 contest for an open U.S. Senate seat. Frank Lautenberg, who long held the seat, died in June.